Work carrier hook



April 9, 1957 J. v. DAVIS 2,787,969

WORK CARRIER. HOOK Filed Feb. 16, 195:

INVENTOR. J g v, any/.5

WORK CARRIER HOOK John V. Davis, Detroit, Mich., assignor to The Udylite Corporation, Detroit, Mich., a corporation of Delaware Application February 16, 1953, Serial No. 337,047

8 Claims. (Cl. 104-93) The present invention pertains to a novel work carrier hook adapted to ride on the rail of a plating machine or other apparatus in which work is conveyed. More particularly, the invention is concerned with a hook for a flat rail.

Although the flat rail has some advantages, it is objectionable in having a large area of contact with the hook thereon, resulting in high friction which presents a difiiculty in starting the hook in motion. The start is jerky and causes the work suspended from the hook to swing rather widely, with objectionable results especially in liquid baths.

The principal object of the invention is to provide a fiat rail hook that starts more smoothly and also stops more smoothly. Another object of the invention is to provide a construction that enables a variable or predetermined disposition of the load on opposite sides of its center of gravity.

in the accomplishment of these objects, the hook has the usual inner surface that normally lies on the upper surface of the fiat rail. A modification is made by providing the top or body of the hook with a friction reducing device such as a roller which extends slightly below the aforementioned surface of the hook and also rides on the upper surface of the rail. This device is forward of the center of gravity line and consequently lifts the aforementioned surface of the hook from the upper surface of the rail except at a rear transverse line called the drag point or drag line.

Thus, the friction between the hook and the rail is materially reduced at all times. Moreover, at the start, the pushing force on the hook and the inertia of the load combine into a resultant force that further reduces the pressure of the drag line on the rail. A smoother start is thereby obtained. On stopping, the forces are reversed, with an increase of pressure between drag line and the rail, resulting in a braking action and a smoother stop.

The friction reducing device and the drag line are at opposite sides of the center of gravity line. By varying the distance of these two elements from the center of gravity line, in the construction of the hook, the distribution of the load on opposite sides of the center of gravity line may be predetermined.

The invention is fully disclosed by way of example in the following description and in the accompanying drawings in which:

Figure 1 is a plan view of the hook;

Figure 2 is a side elevation;

Figure 3 is an end View;

Figure 4 is a side elevation of a modification; and

Figure 5 is a perspective view of a pusher.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

In Figure l is shown a flat horizontal rail 1 of a plating or other conveying machine. In the case of a plating machine the rail 1 is the cathode rail. On the rail is slidably mounted the top portion 2 of a work carrier hook nited States Patent 0 is 2,787,969 Ce i atented Apr. 9 1 9 57 having a pair of holding flanges 3 extending beneath the rail to prevent tilting of the hook. A shank 4 extends downward from the top of the hook at one of the lateral edges of the rail, swinging inward toward the central vertical plane of the rail, and is formed at its lower end with a hanger element 5 from which a work piece or a work rack is suspended, as well known in the art.

A tongue 6 extends from the top portion 2 of the hook forwardly in the direction of travel and over the rail as shown in Figure l. A shaft 7 passes through the tongue transversely of the rail and carries a roller 8 at each side of the tongue for riding on the rail. The outer end of each roller is formed with a flange 9 lying adjacent to a longitudinal edge of the rail, for guiding purposes.

The inner surface of the hook that would normally ride on the top of the rail 1 is designated by the numeral 10 and for convenience will be termed the on-rail riding surface. The rollers 8 extend slightly below the plane of this surface, with the result that the rear end of the hook engages the upper surface of the rail along a transverse line 11 called the drag point or drag line. The rollers 8 need project only a very small distance, theoretically, below the surface 10. The extent of this projection may be A of an inch where the distance from the shaft 7 to the rear end of the hook is about three inches.

In starting the hook forward from a standing position, the moving force is indicated by the arrow a, and the inertia of the loaded hook is indicated by the arrow 12'. The pushing force of a conventional pusher A is obviously the greater, and the resultant force tends to lift the drag line 11 off the rail without, however, actually doing so. Nevertheless, the friction between the drag line 11 is reduced, and an adequate sliding engagement for electrical contact is maintained. The starting effort is reduced, thereby avoiding a jerky start, and the frictional drag is reduced throughout the movement. When the hook is stopped, the aforementioned forces are reversed, the stopping force being rearward and the momentum of the loaded hook being forward. The resultant being also reversed, increases the friction between the drag line 11 and the upper surface of the rail, to provide a braking action and a more gradual stop. The smoother starts and stops reduce the undesirable swinging of the load on the hanger portions 5.

The point of suspension 12 in the hanger 5 may be regarded as the center of gravity. If the vertical line at therethrough bisects the distance between the shaft 7 and the line 11, the load is equally divided between this line and the rollers.

The hook is used on a closed or endless rail and travels at all times with the rollers 28 forward. The pusher at the arrow a is of a type known in the art as in United States Patents No. 2,440,019 of April 20, 1948, and No. 2,479,322 of August 16, 1949.

In the modification shown in Figure 4, the shaft 7 is closer than the drag line ll. to the center of gravity line x. In this particular illustration, the distribution of weight is on the rollers 8' and 25% on the line 11'. Thus, the provision of the rollers enables any desired distribution of weight, according to the relative distance of the rollers from the center of gravity line x.

Other advantages of this hook are its ability to carry heavier loads than other friction hooks of the same size and at the same time to maintain adequate sliding and electrical contact with the rail, in addition to the starting and stopping characteristics already discussed.

Although specific embodiments of the invention have been illustrated and described, it will be understood that various alterations in the details of construction will be made without departing from the scope of the invention as indicated by the appended claims.

What I claim is:

1. YA work carrier hook comprising a top portion having an inner surface, said inner surface being adapted to be operatively positioned directly over the upper surfaceof a horizontally extending fiat rail, a friction reducing member carried by said top portion "at a point to one side of the vertical axis through the center of gravity of the hook, said friction reducing member having a portion projecting below said inner surface, whereby to hold the inner surface of the hook raised from the flat upper surface of the rail except along a transverse line on the other side of said vertical axis, said projecting portion having a rail-contacting area substantially less than the area of said inner surface, and a hook portion suspended from said top portion.

2. A work carrier hook comprising a top portion having an inner surface, said inner surface being adapted to be operatively positioned directly over the upper surface of a horizontally extending fiat rail, :a friction reducing member carried by said top portion at a point to one side of the vertical axis through the center of gravity of the hook, said friction reducing member having a portion projecting below said inner surface, whereby to hold the inner surface of the hook raised from the flat upper surface of the rail except along a transverse line on the other side of said vertical axis, and a pair of flanges extending from said top portion inwardly toward each other and spaced from said inner surface, whereby to receive the rail between the inner surface and said flanges, said projecting portion having a rail-contacting area substan' tially less than the area of said inner surface, and a hook portion suspended from said top portion.

3. A work carrier hook comprising a top portion having an inner surface, said inner surface being adapted to be operatively positioned directly over the upper surface of a horizontally extending flat rail, a roller carried by said top portion at a point to one side of the vertical axis through the center of gravity of the hook, said roller projecting below said inner surface, whereby to hold the inner surface of the hook raised from the fiat upper surface of the rail except along a transverse line on the other side of said vertical axis, and a hook portion suspended from said top portion.

4. A work carrier hook as set forth in claim 3, further characterized by a pair of flanges extending from said top portion inwardly toward each other and spaced from said inner surface, whereby to receive the rail between the inner surface and said flanges.

5. In combination, a horizontally extending flat rail, a work carrier hook comprising a top portion having an inner surface, said inner surface being operatively positioned directly over the upper surface of said rail, a friction reducing member carried by said top portion at a point to one side of the vertical axis through the center of gravity of said hook, said friction reducing member having a portion projecting below said inner surface, whereby the inner surface of said hook is raised from the flat upper surface of the rail except along a transverse line on the other side of said vertical axis, said projecting portion having a rail-contacting area substantially less than the area of said inner surface, and a hook portion suspended from said top portion.

6. The combination set forth in claim 5, further characterized by a pair of flanges extending from said top portion inwardly toward each other beneath and slightly spaced from the bottom surface of said rail.

7. In combination, a horizontally extending fiat rail, a work carrier hook comprising a top portion having an inner surface, said inner surface being operatively positioned directly over the upper surface of said rail, a roller carried by said top portion at a point to one side of the vertical :axis through the center of gravity of said hook, said roller holding the inner surface of said hook raised from the flat upper surface of the rail except along a transverse line on the other side of said vertical axis, and a hook portion suspended from said top portion.

8. The combination set forth in claim 7, further characterized by a pair of flanges extending from said top portion inwardly toward each other beneath and slightly spaced from the bottom surface of said rail.

References Cited in the file of this patent UNITED STATES PATENTS 501,333 Gay et a1. July 11, 1893 1,720,690 Preble .1.. July 16, 1929 1,828,603 Holley Oct. 20, 1931 2,440,019 Pianowski et al Apr. 20, 1948 

